Conventionally, for the amplification and quantification of nucleic acids included in a sample derived from a living body, nucleic acid amplification techniques such as polymerase chain reaction (in the following, PCR), which is a technique that needs temperature changes in course of amplification and detection in a reaction solution, and a loop-mediated isothermal amplification method (in the following, a LAMP method), which is a technique that does not need temperature changes in course of amplification and detection in a reaction solution. In PCR, it is necessary to periodically change sample temperatures generally in two or three types of temperature ranges for nucleic acid amplification. For example, in a typical PCR method, a sample is heated at a temperature of 94° C. to separate a double strand into single strands, annealed at a temperature of 60° C., and kept at a temperature of 60 to 72° C. for a few minutes. The PCR process is repeated for n times to amplify a target nucleic acid of an object. On the other hand, in the LAMP method, reactions proceed at a constant temperature, at a temperature of 60 to 65° C. In the LAMP method, amplification is performed at a certain constant temperature range as described above. Since it is important to accurately control the temperatures of a plurality of reaction tubes at a predetermined temperature, the present invention is also applicable to the LAMP method. Moreover, the amplification temperature is sometimes different depending on samples.
In order to implement this periodical temperature control method in PCR, in Patent Literature 1 described below, an apparatus is disclosed in which the apparatus includes regions, in which the temperature is kept at different set temperatures, and a disc-like sample holder and the temperature of a sample is periodically changed by rotating a disc.
However, in PCR, temperature and time necessary for an annealing reaction to bind primers having a complementary sequence to a base sequence to be detected are different depending on sequences. Moreover, temperature and time necessary in an extension reaction are different depending on enzymes to be added. Thus, in order to simultaneously process base sequences to be detected, that is, a plurality of reaction solutions in different protocols, it is necessary to provide a nucleic acid amplifier, in which temperature and time defined by a protocol is set, by the number of protocols to be simultaneously processed.
Furthermore, such a technique is known in which a plate is included to hold a plurality of samples and the temperature of the entire region of the plate is uniformly controlled. However, in PCR, a single temperature cycle is formed of a denaturation reaction, annealing reaction, and extension reaction, a certain number of cycles is repeated, and then analysis is ended. In the technique in which the entire region of the plate is uniformly controlled at a constant temperature, a new sample cannot be started for analysis after starting analysis of a sample, even though the new sample is in the same protocol, and it is necessary to wait for the end of analysis. Thus, the technique has a problem in that analysis time until the analyzed result of a new sample is obtained is prolonged.